No problem, let's work through this together. We're starting with 210 and 7142 and adding them all up.

Step 1: We'll start by adding the digits 0 & 2 in column 1 and get 2.

Step 2: We'll start by adding the digits 1 & 4 in column 2 and get 5.

Step 3: We'll start by adding the digits 2 & 1 in column 3 and get 3.

Step 4: We'll start by adding the digits 0 & 7 in column 4 and get 7.

So, 210 + 7142 = 7352.

